SLC39A6 and breast cancer: In METABRIC cohort, Similar results were obtained for SLC39A6 mRNA, as high SLC39A6 expression was associated with favourable BCSS in both the entire BC cohort and ER + tumours (P < 0.001 and P = 0.041; Supplementary Fig. 4), but not in ER- tumours (P > 0.05).